The present invention relates generally and in various embodiments to communications apparatuses, systems, and methods. More specifically, the present invention relates generally and in various embodiments to instruments for testing telecommunications lines.
Although various implementations of the present invention, among many, may be described herein with reference to the specific illustrative embodiments related to particular applications, those skilled in the art will understand that the invention is not in any way intended to be, nor should be, limited to such embodiments and/or applications. Those having ordinary skill in the art and reference to the description of the embodiments disclosed and described herein will recognize that additional modifications, applications, and other embodiments may fall within the scope of the claimed invention, and that there may be additional fields in which the present invention may be practiced.
Conventional communication test equipment may be used to test telephone, data, HVAC systems, and security or fire alarm systems using a tone generator. The tone generator is connected across one end of a pair of communications wires and emits a continuous or an alternating tone into the wires. A probe is used at the other end of the wires to identify the wires carrying the tone signal. Thus, a communication cable containing a plurality of wires may be tested for broken wire pairs, continuity, short circuits, open circuits, crosses, and imbalances in the wires. The tone generator also may provide battery power for communicating across a vacant, e.g., unused, pair of wires.
Telephone company technicians use tone generators to test new or existing telephone line copper wire pairs running from a telephone interconnection site (cross-box) to a junction box (serving terminal) located high on a telephone pole or on the ground near an end user residence or facility. The telephone line is usually tested because of the uncertainty of whether the copper wire pairs that are assigned by the telephone company are actually available for services. Oftentimes, the wires assigned to provide the telephone service are either open or may be dedicated to another line with no record of it back at the telephone company. When a candidate copper wire pair is not available for service as prescribed by the telephone company, the technician obtains a new list of candidate copper wire pairs from the records department at the telephone company and proceeds to identify which of the candidate copper wire pairs are suitable for provisioning the telephone service.
In order to test a telephone line, the technician uses a list of candidate copper wire pairs and, between the cross-box and the serving terminal, located between the central office and the end user verifies continuity of the new wire pairs (e.g., testing for short circuits and/or open circuits in one or both of the copper wire pair), identifies wiring faults, determines line polarity, and the like, until a continuous pair of copper wires is found that have no shorts, grounds, opens, crosses or imbalances.
Once the obviously bad candidate copper wire pairs have been identified, the technician begins a final test phase that includes applying a test tone signal to one end of a candidate copper wire pair in the cross-box. In the case where the serving terminal is located on a telephone pole, the technician then climbs up the telephone pole to the serving terminal to monitor the copper wire pairs using a probe or a handset to identify which copper wire pair is carrying the tone signal applied to the wire pair at the cross-box. If the technician cannot identify the wire pairs at the serving terminal, he must climb down the telephone pole go back to the cross-box and connect the tone generator to another candidate copper wire pair and return to the serving terminal and again trace which wire pair is carrying the tone signal. This process is repeated with due diligence until the technician identifies a good pair of copper wires for provisioning the telephone service to the end user.